1*2*3+2*4*6+...10*20*30/2*3*4+...+20*30*40
1+2+3+4+10+20+30+40+1234=?
4.{1,5,10}{2,10,20}{3,15,30}{4,20,40}{ }.
1*2*3+2*4*6+3*6*9+.10*20*30 ______________________________ 2
有一列数组:(1,5,10),(2,10,20),(3,15,30),.
找规律(1,5,10),(2,10,20),(3,15,30),(4,20,40),( ,,)
10/(1*2)+20/(1*2*3)+30/(1*2*3*4)+40/(1*2*3*4*5)+...+90/(1*2*
10/(1*2)+20/(1*2*3)+30/(1*2*3*4)+40/(1*2*3*4*5)++...+90/(1*2
解方程组:x/2+y/3=1 x*20%+y*30%=14*10%
1=10 2=20 3=30 4=40 5=50
找规律1,60,2,30,3,20,4,15,5( ),6,10
1+2+3+4+5+6+7+8+9+10+20+30+40+50.+100